TAMPA, Fla. — In the modern era of campaigns, candidates in competitive races can’t go anywhere without someone from the other party following them with a video camera — and the party conventions are no different.

Fewer GOP House and Senate candidates made the trek to the Republican National Convention here in Florida, and few Democratic candidates in competitive races are expected to attend the Democratic National Convention next week either. While some of them want to avoid the headache of being tied to the unpopular national parties, there is a new excuse emerging — the proliferation of trackers.

Democratic trackers are following GOP candidates here in Tampa and, according to GOP strategists, there will be GOP trackers following Democrats in Charlotte next week.

Trackers are an increasing worry for both parties, although Democrats have done a better job at embracing the intense, yet effective, form of opposition research.

American Bridge, the Democratic outside group that has focused its efforts on filming GOP candidates, has trackers across the country in both House and Senate races, and one dedicated solely to Florida. It also has several on the ground here. Both Democratic campaign committees also have trackers at the RNC.

In reality, it’s virtually impossible for these videographers, always on alert for a misstep or verbal slip-up, to get into the security perimeter, lined by Secret Service agents followed by state and local law enforcement, where the main, official events are held. But candidates also attend events and fundraisers around the area, outside the security perimeter, and that’s what feeds strategists’ nervousness.

According to one party operative, trackers have been directed to follow candidates in “public events in public spaces.”

“I think they’re not wrong to be worried about [trackers],” said one Democratic strategist this week. Even if trackers can’t get into the convention, they could still try to get candidates outside the perimeter “embracing national Republican brand in Congress which is toxic.”

Former governor and current Senate nominee Tommy Thompson (R) attended the Wisconsin “Beer & Brats Bash” on Wednesday afternoon, outside the perimeter, and said potential trackers weren’t the reason he didn’t take the podium to deliver public remarks to a favorable crowd, noting he’s given remarks at the last four conventions.

“I think it is absolutely sort of a dismal display when you have trackers following people,” Thompson said in an interview with RPR after the event. “I think the Democratic Party is noted for that. I think it shows a lack of respect for the system and it shows they don’t have anything else to run on when they’re trying to find somebody saying something or a mistake, which to me is a poor way to run a campaign.”

Overall, only a fraction of House and Senate candidates made the trip, and fewer were given the opportunity to speak from the stage. On Tuesday afternoon, Deb Fischer, heavily favored to win the Nebraska Senate race, and Rep. Rick Berg (R-N.D.), who finds himself in a tougher-than-expected Senate contest with Democrat Heidi Heitkamp, both addressed a small crowd. Texas Senate nominee Ted Cruz, a virtual lock to win his race, spoke in primetime on Tuesday, and Thursday evening home state Senate candidate Rep. Connie Mack (R-Fla.), will take the podium.

Thompson and other Senate candidates, including Arizona Rep. Jeff Flake (R), who won his primary on Tuesday, and Massachusetts Sen. Scott Brown (R), have been seen at the convention but have maintained lower profile schedules, such as delegate or official events.

Next week, Democrats have just three Senate candidates and one House candidate (not including current Congressional lawmakers) so far on the list of speakers at their convention in Charlotte.

To these Republican candidates, now under even increased pressure to win back the Senate, the trackers are more of a hassle than a real threat. The candidates are constantly under surveillance, whether they’re at the RNC or at home on the campaign trail. Unless they’re doing something incredibly damaging, most strategists would rather have their candidates being filmed talking to local civic groups or voters at home rather than throwing red meat to their base, and both parties’ leaders have publicly given candidates permission to take a pass on trips to Tampa and Charlotte.